Carbon black process and apparatus



PatentedV May-'115, 1945 ORBN BLACK PBCESS AND Jolseph Crxreici, Kaw,Okla., assigner to Phillips trolemn '(loi'npany, a corporation o! Deia'-apuestan .March 21, 194s, serial No; 436,524

14 claims. (ci. 2x4-209.8)

N. 424,084, led December 22, 1941, and Serial No. 431,171, nledfFebruary 16,1942. At the present time. most oi' the carbon blacks o tcommerce' are produced by a very few processes and these blacks may begrouped into classes depending upon the types of rubber compound in themain reaction chamber in which the tan-` gential flow of gases isutilized. In this improved process the preheating is advantageousbecause.

without preheating .any o f thereactantsentering the intermediatechamber, this .chamber vcould carry out its functions only to a extent.l

The principal object of this invention is to provide an apparatus and aprocess for `producing carbon black of high yield and of high qualitycomparable to or superior to the resent day I channel black for use intire stoc and vulcanized rubberv whlclithe carbon blacks will producer-A soft carbon black as compared 'to a hard carbon black is one whichwhen mixed in a conventional rubber compound andv `then vulcanizedyields a productwhich is softer, more resilient, more .rubbery and yettough whereas a hard carbon black in the same compound imparts stiiier,'tougher characteristics, with lower resistance.

These two types of carbon black may be considered essentially as limits"and many of the carbon blacks produced will possess hardness propertiesintermediate these above limits.

haldtype carbon black which is especially good for compoundingautomotive tire tread stocks that withstand abrasion and possess goodphysical test properties. However, the yield oi carbon by this processis only about 3.5% of the carbon content oi' the gasfrom which it ismade. Some 'other carbon black processes give higher yields Thecommercial channel" process produces a A.

of carbon than the channel process, butin essentially all cases theseblacks are of a softer type and less desirable for use in good qualitytire tread stocks. These latter blacks, however, iind other and varieduses, which are min-or as compared to the relatively large amounts oi'hard channel -black which go into'tires at the' present time, and aprocess which would give a high yield of a hard black similar to channelblack in properties,A would be most desirable.

' The present invention comprises'improvements of the process andapparatus disclosed in the aforementioned copending applications. In onespecillc embodiment, it comprisesfthe use of an insulated reaction orsoaking chamber (to beA referred to hereinafter as an intermediatechamber) that is ahead ol the main reaction chamber and Vthatincidentally serves as the inlet tube to the latter, In a preferredform, my improved process as herein disclosed comprises (1)Y apreheating'step, (2) an'intermediate soaking or partial combustion inwhich the temperature and/or the content of unsaturated hydrocarbonsisincreased, (3) and the conversion to carbon black Another object l'this invention isto improve vStill another object oi' this invention istoprovide a carbon black making process which is ilexible in operationand especially in the respect that a product of essentially any desiredproperties ranging from those ofthe conventional soft. carbon blacks,through the 'intermediate blacks, to

thehard channel blacks, orA` even harder, can vbe produced with the sameapparatus and raw materials merely by alteration and control of theoperating conditions.

Other specific objects oi the present invention are: to increase theyield of carbon black, to improve the quallty'oi the carbon .black,*tolower the amount of tangential fuel required in the main chamber toproduce a given yield of carbon black of any given quality, and to lowerthe preheat temperature required to lgive any given results.

Still other objects andadvantages will be apparent to those skilled inthe art from a careful study of the following description anddisclosure: In the accompanying diagrammatic drawing, which is a part ofthis specication and which illustrates a preferred form of the apparatusfor carrying out my invention,

Figure l is a longitudinal section of a 'preferred form of the reactionchambers with the preheath ing equipment in diagrammatic form.

Figure 2 is a cross-sectional view ofthe' pre- Figure 4 shows indiagrammatical form a vpreferred method of addition of the heavy gas oili'eed to my. carbon` black making apparatus.

Like numerals on the several figures refer to conventional andwell-known parts as valves, flow meters, pressure regulators,temperature measuring devices, etc., for simplicity have not been shown.i Referring to the drawing, cylindrical reaction chamber I has a liningli of a highly refractory material such as sillimanite, an aluminumsilicate or alundum, an` artificial oxide of aluminum. Likewise,cylindrical intermediate chamber or reactor 34 has a lining 35 of ahighly refractory material, and may well be of alundum also. Betweenrefractory liners Il and 35 and cylindrical steel shell I3 is, a layerof insulating material I2. Chamber lli is equipped with one or more fuelburners l5 extending through the chamber wall and terminating in anovalfshape opening such that the incoming gaseous fuel mixture entersthe reaction chamber tangential to the inside cylindrical surface of thechamber and in a plane normal to the longitudinal axis thereof. The useo'f several tangential burners has been found advantageous in somemodifications, and particularly' in rction chambers oi large diameters.lheburner nearest the inlet end of the chamber preferably is larger thanthe others, since it has been found advantageous to introduce most ofthe fuel near the inlet end of the chamber. Opening or openings 20 arefor observation and temperature measuring purposes. y

At its inlet end, chamber u is equipped with inlet tube i8 which is inline with the longitudinal axis of said chamber. If only one gas isadmitted tothe inlet end of the chamber, tube I0 extends through therefractory, the insulation, and the shell but in case a mixture lof twogases is admitted, a Y I9 is used. the reactant gas entering through gasleg IB and thevreactant air through air leg il, the .tube lli serving asa mixing tube as well as 'the chamber inlet tube. Cham ber 84incidentally serves `as the inlet tube to chamber l0, the eiliuent ofsaid reactor 34 passing directly into the said chamber I0. 'I'helongitudinal axes of tube i6 and chamber 34 and l0 are in line.

l'I'l'ie reactants, such as, for example, natural gas and air with lessthan sufficient air for complete combustion, in one method of operationenter the system through the gas inlet tube 2B and the air inlet tube28, respectively, and are preheated in furnace 25 in pipe coils 21 and28 and pass from this preheat furnace through pipes 23 and 24 into theintermediate reactor 34, the

- emuent therefrom passing directly into chamber i0. The reactionproducts exit from the discharge end of chamber i0 and are cooled by anyconventional means, such as by a water spray I4. The carbon black aftercooling in cooling section 2i is transferred through conduit 22 and isseparated from the gas by any carbon collecting sys'- tem such as abaghouse 33.

In case gasoil is used as a source of carbon, this vhydrocarbon liquidis pumped by pump 30 through line 3| and atomized by atomizer 32 intothe preheated reactant gas pipe 23 as in Figure 3. or in case the gasoil is fed directly into the intermediate reactor, the oil is pumped bypump I0 through line 3| and atomized directly into the intermediatereactor 34 by atomizer or sprayer l0, as shown inFlgure 4. i

In'the preferred method of operation of my invention, a mixture of fuelsuch as natural gas and air is introduced through tangential burners ilat sufficient velocity as to cause the fiameeto adhere to the insidesurface of chamber l0 and to form a blanket of flame and productsof'combustion overthe chamber wall throughout its length. vThe velocityof the incoming fuel mixture through the tangential burner ports mayvary over" wide limits, but must necessarily be rather high to maintainby centrifugal force the blanket oi' flame and combustion products. The

. latter travel from the tangential burner inlet toward the outlet endof chamber I0.' following a helical path adjacent the inside wall of thechamber, thereby forming substantially a continuous layer or blanket offlame and combustion products on the inside wall.` This layer or blanketserves as a separating medium to prevent contact of the central contentsof the chamber with the chamf ber walls. Furthermore, in order toprevent Bashback, the velocity of the tangential fuel through the burnerports must be higher than the linear rate of ame propagation of the fuelmixture used. I havefound that this velocity of tangential fuel iiow mayvary from as low as 30 feet per second to 200 feet per second, or. evenmore. In one series of experiments, best results were'obtained bymaintaining this velocity within .the range of 100 to 150 feet persecond, or, ash-back mayfbe prevented by mixing the tangential air andtangential gas at the tangential burner ports Il."

'Ihe preheating furnace' may be a tube furnace or .other type of furnaceor heating means of suitable design, such that the gases undergoingpreheating may be heated to temperatures within the range of say 1000 to2600o F. and such that the heated gases may be at a predeterminedtemperature so that the operation of my invention maybe properly carriedout. l

v The preheated carbon-bearing gas, such as natural gas or a mixture ofsuch 'gas and a preheated oxygen-bearing gas such as air, enters chamber34 through tube I8. If the mixture is used. inlet of the intermediatechamber 34.

and gas, such mixing increasing the eectiveness The carbonbearing gasand the oxygen-bearing gas passed through tube i6 arehereinafter'referred toas the reactant gas and the reactant air.respectively.

The chief function ofthe intermediate chamber 34 is to raise thetemperature and/or the content of unsaturated hydrocarbonsv in thereactants before they enter main reaction chamber III. Chamber I4 servesas asoaking chamber if a reactant gas alone is admitted into it throughtube I0 and in addition as a partial combustion chamber if a mixture ofreactant gas and reactantair are admitted. In the first casepthe purposeof the chamber is to give the reactant gas additional time for crackingprimarily to unsaturated hy' drocarbons; in the second case. anadditional purpose is to further the cracking and preheating of thereactants by utilizing heat furnished by combustion of a part of thereactant gas. A'I'h'e time-temperature conditions in thechamber are soregulated as to favor formation'of unsaturated hydrocarbons withoutforming extensive amounts of carbon, which would tend to accumulate inthis chamber. The time of reaction in the chamber may vary from a fewthousandths of a second up to one second, or even more, depending on therichness of the reactant gas, the preheat temperature of the reactantgas and of the reactant air, the ratio of reacant air to reactant gas.and other factors. Since chamber I4 serves as the inlet tube to chamberI this function must be considered in selecting the diameter of chamber3l. ameter for chamber 3l was found to be one which In several cases, asuitable di- (reactant gas) containing 35 pounds of carbon per 1000cubic feet, with my apparatus and in accordance with my process. All theexperiments reported herein were made in a reaction chamber anyparticles do come in contact with the walls, they are swept away by thehelicaily traveling tangential name.

'Table I shows operating data taken during the gave the gases in thechamber a linear velocity 5 0f 9*/2 inches in diameter and 45 inches10118 and of the same order of magnitude as the linear with threetangential burners, 1, 6, and 11 inches downstream velocity of the gasesin chamber In, from the inlet end of said chamber I0. 'I'he tlrstChamber I4 directs its eluent along the longiand third burners werelocated as shown in F18- tudinal axisjof chamber l0; this directingeffect, ure 1: the second burner Shown in Figure 2 was in addition tothe entect 0f the tangential name, 10 half way between the rst and thirdburners and lwhich keeps the reactant gas away from the at 180 aroundthe circumference from them. walls oi the chamber assures that thereaction to About half 0f the tangential fuel was used in the rbonbmcktakes pm in the central core of first burner, and the remainder wasdivided apghgmber n, proximately equally between the otherl two. As'I'he retention time in chamber Il) can be Varied 15 indicated in theSeCOnd COlumn 0f the table. in over wide limits. In one experiment thetime was Seme of the experiments en intermediate chemapproximately o isecond. Although this parber 34 was not used, tube i6 emptying directlyticular retention time was held to about 0.1 secinto Chamber l0; inOther experiments, an interond, it was found that the retention time maybe mediate Chamber 2V2 inches 1n diameter by 16 varied, depending uponother conditions, from apinches in length 01 3 inches in diameter by 32proximately 0.005 second to as long as 0.4 second, nGheS 1D length WHSused Tube I3 in B11 Cases or even one second, and still obtain carbonblack WBS 011e inch in inside diameter and W0 inches in o! good qualityand high yield. length. In the yield columns of the table, the Thetemperature within chamber m may be higher values in the one column werebased on the varied within wide limits. For example; the rectant gas andin the other column, the lower chamber temperature in theabove-referred-to Yields was based on the total 83S used. which WBSexperiment was varied within the range of 2000 the reactant gas plus theSaS in the tangential to 3300 F. Optimum yields of excellent qualityfilel- This Same natural 88S WBS Used RS reaitnt carbon black resultedwhen the temperature was gas and as tangential gas. The reactant ses andof the order of 2300 and 2600 F.: however, high 30 reactant air wereheated individually but in the y yields were obtained at chambertemperatures as same preheat furnace and to the same temperahlgh as 3100F., and at temperatures lower than ture, as recorded in the third columnof the table. 2200 F. Thus, it can be seen that chamber tem- It might bementioned that the tangential burnerr perature is not a highly criticaloperating confuel was composed of air and gas in the theoretical ditionand that it can be varied within very wide ratio for complete combustionto carbon dioxide limits during the production of extraordinarily andwater, although this exact ratio was notnec high yields of carbon black.essary for the successful operation ot the process.

` TABLE I l Operating data Reactants, Fuel to Intermed Preheat cu ft'per hr' cuPiltnpeers'hr. Yield'lbs'MCF Run Nos. chamber, fm

Inch n Reactant Tow (las Air Gas Air gas basis bgrs B200 Non 2,000 1,2000 000 0.000 0.2 0.1 B243 2%110- 2.000 1,200 0 000 0000 1&1 as

B210 Non@ 1,000 1,200 n 100 1,100 4.0 3.1 B234 254110.. 1,000 i, 200 0100 1,100 0.5 4;1 11320 0132.-... 1,000 1,200 0 000 0,000 0.4 3.0

B221 None 1,000 1.200 000 10o 1,100 2.3 2.0 1323s 25x10 1,000 1.200 000100 1,100 4.0 :1.0 B020 3x32 1,000 1,200 000 000 0,000 4.0 3.1 B030 3x321,000 1,200 000 500 0,000 5.1 4.0

B212 None 1,000 000 0 000 0,000 0.0 :1.4 B200 214:10... 1.000 000 0y 00o0,000 5.2 :1.0 11302 3x32 1,000 000 0 000 0.000 4.2 a0 13330 3x32 1,000000 0 400 4,400 0.0 3.0

The herein disclosed tangential flame serves In all the runs of Table Ithe amount of tanseveral purposes, and its proper use makes possigentialfuel used was suillcient to keep the wall ble continuous operation of myprocess and apof chamber I0 free of carbon except in run B333, paratuswithous deposition of carbon on the in which a thin layer of carbon wasdeposited on chamber walls. The flame covering the walls G5 the wall inthe last half of the chamber. No carserves as a mechanical separator orpartition to bon deposited inside of the intermediate chamber preventcontact of the reactant gases with the 34, or the amount was so small asto be unnoticed. chamber walls. Furthermore, any particles of A study ofthe results in Table I reveals that the carbon which may get into thelayer oi flame are use c! the intermediate chamber or reactorimsubjected to the water-gas ieaction; and, in case proved the yield ofcarbon black in most cases; lowered the amount of acetone extractablematter in the product (see Table III), and particuiarly in the case oi'the 3 x 32 inch intermediate reactor lowered the amount oi.' tangentialfuel remanutacture oi carbon black from natural gas quired in chamberi0. One of the most importantresults of the use of an intermediatecharnber vis the lowering of the preheat temperature l required toproduce carbon black of any given quality and yield, or to improve thequality and yield of carbon black made from reactant gas of the samepreheat temperature over that made without the use of the intermediatechamber. The superiority of the 32 inch intermediate chamber or reactorover the 16 inch one demonstrates the value of additional soaking andreaction time before the final reaction in the carbon producing chamberI 0.

My process is not limited to the use oi natural' gas as the carboncontaining gas or to condensable hydrocarbons or even to normally liquidhydrocarbons since hydrocarbons as heavy "as gas oils may be used.Several experiments were made and reported herein in Table II using arecycle gas oil as the carbon containing material. This by the preheatedair or by partial combustion of the reactant gas in the tube i6. If theapparatus embodiment of Figure i is used and the heavy carbon-containingoil added as at point il in the embodiment shown in Figure 4, thepreheat furnace heats the reactant gas and furnishes a part of the heatfor the vaporization of the oil, the remainder being furnished by thepreheated air or by partial combustion of the reactant gas in theintermediate chamber Il.

.Table II below shows the operating data taken when manufacturing carbonblack from natural gas (reactant gas) containing pounds 0i' carbon per1000 cubic feet and a recycle gas oilof 18.4 A. P. I. gravity when usingmy apparatus and according to my process as herein disclosed.

In these experiments alsothree tangential burners were used in chamberlil in the same relation as above disclosed. d TABLE II Operating data[9% by 46 inches reaction chamber with 41,5 by 16 inches intermediatereactor] Fuel to burn- Refftgt'lrfu ers, cu. it. per Carbon black y' hr'Gas oil tate, Temp., gala/MCF Run No. F "f gigant Yieid mend Gas Air GasAir n, E-H/MtmtF vllfgn gu basis llaa/gaf.

soo soo ooo s. soo o n.1 800 800 600 6, 600 1. 18 12. 4 7. 4 800 lB00600 6, 600 3. 75 25. 3 5. 7

l, m0 1, 120 700 7, 700 (l 3. 9 l., l, m0 l, 080 700 7, 700 1. 38 11. 4.5. 4 l, 200 l, 080 700 7, 700 3. 05 n. 3 6 0 gas oil was atomized orsprayed as a fine mist into my carbon black system as at point 32 ofFigure j3 or as at point 36 of Figure 4. Complete Vaporiz- 1 ation ofthe oil is conductive to formation of small particle carbon black,whereas, if the oil entered reaction chamber l0 in the form of droplets,

Y and point of addition of the oil are of primary importance. On theother hand, the time of heating of the oil must not be too long as thiswould lead to` excessive cracking of vthe heavy oil and plugging ot thepreheated reactant gas tube with carbon. Addition of -a heavy crackingoil to the reactant gas inlet 29 of the preheat furnace would materiallylower the temperature at which the preheat furnace 25 could be operated.Ii the oil is added directly to the intermediate reactor as at point 36of Figure 4, the reactor or intermediate chamber 34 must be sufficientlylarge to permit complete vaporization of the oil, but not so large as t0allow excessive formation of carbon from the oil in this portion of theapparatus. I have found that this latter point of addition of such heavyoils as the herein disclosed recycle gas oil is to be preferred. It isapparent thenthat the preheat step in my process plays a double role andis definitely interrelated 'with the gas oil or heavy hydrocarbonaddition step. If this apparatus embodiment lof Figure 1 is used and thecarbon containing oil atomized into the preheated reactant gas as in theembodiment of Figure 3, the

preheat furnace not only preheats the reactant' About half of thetangential fuel as in the other experiments was used in the burnernearest the inlet end and the remainder was divided about equallybetween the other two burners. In column 8 of this Table II headedcarbon black, yield, lbs/MCF reactant gas basis aregiven the poundsyield oi' carbon black per 1000 cubic feet of reactant gasdisregarding'the feeding or time rate of feeding of the gas oil into thepreheated reactant gas. The blending values for the gas oil wereobtained by subtracting the yield of carbon black from the reactant gasalone in the blank experiments in which .no gas oilwas used from theyield from the reactant gas plus gas oil (column 8) and dividing thediierence by the oil feed rate per 1000 cubic feet of reactantgas'icolumn 7). In all of the runs reported in this table, the amount oftangential fuel used was sumcient to keep the reaction chamber wall'free-oi carbon The addition of the recycle gas oil. tothe reactants did notmaterially affect the amount of tangential fuel and reactant airrequired to produce a carbon black low in tarry material. All of thesamples produced were low in acetone extractable content as may be seenfrom TableIV. The yield of carbon black from the gas oil was very high,averaging more than 5 pounds carbon black per gallon of oil.

One of the outstanding advantages oi my profi- V ess lies in the factthat although the yield is exceptonally high, the quality is in mostrespects herein disclosed und to compare lu properties lower Lempereture(260' F.) because or their fast with those of channel black, buche; orrubber vulemlzinz prorld'lgg: pelcent.

are ordl t the tollowof Les'. PINIes "u l I4 tls- ;gaorllvue prep d ce nu ured with e Yen-ley osclllomph LS recorded in plm by welsh! 6 thellble. 1.500* edu] u q Smau shut 100 In ble III. m US L er: to the Tnx.:IV

Rubber test1 huno Itu- Mndllul. Bmkd, u penn l noun uw WI.. nq bei.'flung minous ln.

IJ Lm 4.110 45 lm LID G) lm (.566 l) LIU Lm E 1750 1M 11H) :.m l) 3,010tlm In :,w :.m

l! 1M 1T!! klm Lm d) LQ!) 3.0i! l) 3,7m

n 1m 4,275 l lll) LCI) l) ZID 510 l) Lm 025 l) LA!) lll) U 1w L@ N LmLMD l) LW *1W l) 11N lm LIN I. U IMI) 1.1i) I) Km LM l) LII) Lm Lm Lm l)All LM D Lm L Iva-ungarn n-upwqnnumonmeamormxum IMU'nbeleentthnc'ubonbhckumms according tafthe process hereindtsmmmwbmlxedvithwomer totheuctlouchlmberlludmnlnthedn necessarily needto be cylindrical, but may bC more oval in section or even rectangularto NUNC- The tangential burners. in the case of small chambers. may belimited to one, or in larger charnberS mly be two or more, the numberdependln on the sire of the chamber. When several burners are used. theycan be distributed along the length of the chamber, or they can be atthe inlet and distributed around the circumference of the chamber. Inthis latter case. it may be desirable lo give the fuel some velocitydownstream with respect to the chamber by directing the burners at aslightly less angle than 90 to the longitudinal axis of the chamber. Theburner ports can be oi any shape such as round, oval or rectangular. Arectangular burner has an advantage over a round one ln that a greaterportion of the fuel stream enters tangentialiy with respect to theinside surface of the chamber. this being true in the case of burnerswith cross sections having a large ratio of length to width and with thelonser dimension oi' the cro section parallel to the longitudinal axisof the chamber. In one embodiment. a large number of tangential openingsmay be provided in the lining of the chamber and supplied with fuel froman annular space surrounding the lining. In mother embodiment, a singlerectangular burner extending throughout the length of the chamber can beused.

The products issuing from the chamber il can be cooled by anyconventional means. such as mixing with a cool inert gas such asnitrogen, or with a spray of water. 'I'he position of the point ofintroduction of the cooling gases or water spray depends on the desiredtime of exposure o! tl'ie carbon product to the hot gaseous products ofcombustion from the tangential name. I! a separate quenching chamber isprovided for each reaction chamber. it should preferably have about thesame diameter as the chamber and have its axis ln line with the axis ofthe reaction This arrangement permits the tangential name to continueinto the quenching chamber to keep the products in the centralcoreeromcontactingsolldsurfacesimtiitheyare Adiscussionof-the ratiooftholenlthto diameter of the reaction chamber is given ruil! in mypreviously filed applications cited above.

-Qtheraasesthanalrcanbeusedwiththe reaetant fuel as well as with thetangential fuel. f3; example. oxygen-enriched air or even oxygen Aadisclosed heretofore. my process is notlimiiedtotheuaeof'nahsraigasasthecarboncontaining gas. in addition.either dry gas. wet morrawgasas'itcomcsfromthewelLorgasoline-extraction-plant or rennery-'residue gas. heavier hydrocarbons,such as b'utane. or stili heavier ludrocarbon products or fractions. oreven normally liquid hydrocarbons. may be used. as for example. gas oilas above disclosed. Higher boiling oils than the gas oil of commerce maybe used as a source of carbon'. as well as lower boiling oils. auch asthe kerosene fraction. heavy or iight naphthas, or even thegasoline-range hydrocarbons. In addition. auch materials aslow-temperature coal las. coal-tar distillates and oil-shale gases anddistillates may be used as charge stock to my process.

The air or gas. or both. in the fuel to the tanaentiai burners can bepreheated as a means of introducing more heat into the chamber. Puelrich in air. or air alone, preferably preheated. can be used in any orall of the tangential immers.

ranching the said ruei with anwas round to 76 reduce thc luci rais,`required to keep the chamber walls ircc of carbon. When air alone laused ln thc tangential burners. the product has a grayish color incomparison to the very black channel product, but the yield oi carbonblack is high. As desired. the fuel mixture to the tangential burnersmay be allowed to burn within the chamber or in a separate combustionchamber. the hot combustion gases then being conducted tangentially intosaid chamber. Since the functions of the tangential gases are lo iumishheat to the chamber walls and to prevent deposition of carbon thereon,it is immaterial at what point the combustion takes place, as long asthe gases reach the chamber walls In a properly heated condition. Oneadvantage of my process over the prior art lies in the fact that itmakes possible the rapid conversion of hydrocarbons to carbon black outof contact with solid surfaces ln extremely short reaction times andwithout depending on maintenance of streamline flow. I have veriiledthat even under turbulent flow conditions a tanzential layer of gas canbe maintained to separate the wall and the gas occupying the centralcore of a cylindrical reaction chamber. The presence of a tangentialgaseous layer may be readily demonstrated by producing a yellow flame inthe central core and then introducing air through one or more tangentialports, when a clear layer or air adjacent l the wail is visible. Thethickness of this layer changes only little even if the amount of airintroduced is two to three times the minimum required to establish theclear layer. 'I'his additional air over the minimum is apparently mixedwith the reactant gas in the central core. and this fact is evidenced bythe shortening of the yellow llame. If the air were introduced axiallyas a imiform layer next to the wall with a streamline flow in both thecentral dame and the air' layer. a long diffusion name results but aclear layer of alr is maintained the iian'ie and the wall. However. areincreased into the turbulent iiow range. the flame becomes shorter. theclear layer adjacent to the chamber walls disappears, and the flame isthen in direct contact with the wall and carb'on may be depositedthereon. In my process. the operation at suiiiciently hish linearvelocity of reactant sas as to give' turbulent iiow results in rapidtransfer of heat into the moving body of reactant gas 'an'd decreasesthe time af reaction. This decreased time of reaction operatesadvantageously in my a much greater output of carbon black percham'berresults. and a relatively large output of unit of chamber volume ischaracteristic of my reaction chamber and process oi' operation.

Operatinr 'under said turbulent flow conditions in the reactant aasstream has the advantageof making any given cross section of the Itrd'an'i normal to the direction of flow more moseneouawith respect tostates of decomposit'on, com on. and dilution. In contrast. a diffusione. characteristic of other carbon black making' processes. is likely tohave much tar and imrescted gas in the center, i surroimding layer ofsubstantially decomposed gas carrying good quaty carbon, and an outerlayer of completely decomposed gas carryins overheated carbon.

when prcmixed fuel is used in the tangential burners. surface combustionof the chamber walls takes place thereby heating the walls to a veryhigh temperature. These heated walls then heat the reactant gases byradiation. An appreciable part of this surface combustion locs to C: andH10 and does not revert to CO and H: because the carbon formingreactants do not mix completely with the combustion products and becausethe time at elevated temperature is too short.

The tangential flame also has the function oi diluting the products,particularly in the latter part of the chamber. This dilution decreasesthe concentration of any undecomposed hydrocarbons and thus lessens thechance for carbon particle growth between the chamber and the point inthe cooling system at which the products are cooled to a temperaturebelow which no further reaction is possible.

Mixing or the reactant gas and the tangential llame within the chamberitself has been found to play an important role in my process. Inaddition to aiding in heat transfer, such mixing improves the quality ofthe product. as for example, the amount of acetone extractable matter inthe carbon black is readily controlled by regulating the extent of thismixing; the greater the extent oi' mixing. the less the acetoneextractable.

Another advantage of this process over the prior art is its greaternexbility as to controlling the operation and as to control of thequality of product. The properties of the product can be varied over awide range by adjusting the fuel rate to the tangential burner, theratio of reactant air to reactant gas. gas and air preheat temperatures,reaction chamber temperature, and cooling of the chamber product, etc.Using my apparatus and the same raw materials. carbon black varying inproperties from those of s soft thermal decomposition" black to those ofa hard channel black" was produced.

While chambers varying in diameter from four and one-half inches to nineand one-half inches have been successfully used. as disclosed heretoforeI do n'ot wish to limit my apparatus to these sises since other aisesboth smaller and larger may be used. For chambers of large diameters andcorresponding length, such as would be used in commerce, the optimumnumber and arrangement of Atangential burners would need be determined.

llaterails orconstruction, as for example, preheat furnace tubes,reaction chamber insulation and lining. etc., may be selected from amongthose items commercially available and best suited to the operatingconditions as herein disclosed without departing from the scope o! myinvention.

The disclosed values oi.' operating temperatures. retention time, etc.,are not intended to be limitlng conditions, since experiments haveindicated that operating conditions may be varied within wide limitswhile extraordinarily high yields of carbon black of quality in manyrespects equal to or superior to the channel black of commerce areproduced.

While the preferred apparatus and method of operation'for carrying outmy invention are described in this specification, it will be obvious tothose skilled in the art that there may be many possible variations ofthe apparatus and methods of operation ss may be learned from operatingexperience and yet remain within the intended spirit and scope of myinvention, and limited only by the following claims:

I claim:

l. An apparatus for producing carbon black comprising an unobstructedintermediate reactor having a closed inlet end wall carrying an inlettube, a generally cylindrical side wall and an open outlet end; anunobstructed reaction chamber having an inlet end wall carrying an inlettube, a generally cylindrical side wall and an open outlet end, thecross sectional area of the open outlet end being substantially the sameas the cross sectional area. of the cylindrical reaction chamber. thereaction chamber side wall carrying a burner opening near the inlet endwall of said chamber, the burner opening being so positioned as todirect gases passing therethrough in a direction tangent to the innersurface ot the chamber side wall and essentially perpendicular to thelongitudinal axis of said cylindrical chamber; and a cooling chamberprovided with means for cooling the gases directly connected to saidopen outlet end of said reaction chamber for unobstructed passage ofsaid gases thereinto: the open outlet end ol the intermediate reactorbeing the inlet tube of the cylindrical reaction chamber: thelongitudinal axes of the intermediate reactor inlet tube, theintermediate reactor and the cylindrical reaction chamber beingessentially in line and the diameter of the intermediate reactor beingsubstantially smaller than the diameter of the said reaction chamberwhereby additional space is provided in said reaction chamber for tlowof said tangentially directed gases therein without substantialconstriction or enlargement of the stream of gases emerging from saidintermediate reactor into said reaction chamber.

2. An apparatus for producing carbon black comprising an unobstructedintermediate reactor having a closed inletend wall carrying an inlettube. a generally cylindrical side wall and an open outlet end; anunobstructed reaction chamber having an inlet end wall carrying an inlettube. a generally cylindrical elongated slde wall and an open outletend, the cross sectional area of the open outlet end being substantiallythe same as the cross sectional area of the cylindrical reactionchamber, the reaction chamber side wall carrying a plurality of burneropenings at least one of which is positioned adjacent the inlet endwall, the said burner openings being so positioned as to direct gasespassing therethrough in a direction tangent to the inner surface of thechamber side wall and essentially perpendicular to the longitudinal axisof the said reaction chamber: and a cooling chamber provided with meansfor cooling the gases directly connected to said open outlet end o! saidreaction chamber for unobstructed passage ot said gases thereinto: theopen outlet end of the intermediate reactor being the inlet tube of thecylindrical reaction chamber: the longitudinal axes of the intermediatereactor inlet tube, the inter# mediate reactor and the elongatedcylindrical reaction chamber being essentially in line and the diameterof the intermediate reactor being substantially smaller than thediameter of the said reaction chamber whereby additional space isprovided in said reaction chamber for flow o! said tangentially directedgases therein without substantial constriction or enlargement of thestream of gases emerging from said intermediate maintaining thetemperature in the intermediate reactor sulllciently high to crack theremitan?, hydrocarbon to increase the content of unsaturated hydrocarbonwithout formation of carboni lntroducing the eiiluent of theintermediate reactor at a non-peripheral point in the end Wall i Bnunobstructed reactor chamber having im inleiend wall. a generallycylindrical side wall and an Open outlet end. the cross sectional areaof the open outlet end being substantially the same as the crosssectional area of the cylindrical reactor chamber. the intermediatereactor emuent being passed into said reactor chamber along thelongitudinsl axis thereof. introducing a mixture of gaseous fuel and atleast suiilcient oxygen-containing gas for substantially completecombustion of said fuel into the reactor chamber near the inlet end wallthrough a burner port. burning thc fuel-gas and air to maintain thetemperature in the reactor chamber at the carbon black formingtemperature, said burner port being so positioned in the side wall ofthe reactor chamber as to direct the ilow of fuel and oxygen-containinggas in a direction tangent to the inner surface of the chamber side wailand essentially perpendicular to the longitudinal axis of saidcylindrical reactor chamber. the mixture of fuel and oxygeneontainlnggas being introduced through said burner port at suiliciently highvelocity and in sumcient quantity to maintain the flame and combustionproducts by centrifugal force adiacent the whole inner surface of thechamber side wall thus forming a separating layer of said flame andcombustion products between the aide wall and theintermediate reactoremuent in the re actor chamber. cooling the eilluents of the reactor tobelow4 the carbon cracking temperature `and separating the carbon blackfrom the products of 4. ',Ihe continuous-process of producing carbonblack comprising introducing a stream of preheatedreactant hydrocarbonin the gaseous state at .llllncperlpheral Point in the inlet end wall ofan intermediate reactor having an inlet end wall anda generallyelilidrical side wall and an open outlet the jreactant hydrocarbon beinginadirection parallel to the longituor said intermediate reactor, maininthe intermediate suiilciently high to crack the reacta'nt to'incres'sethe 'content of. unsatbydrocarbonwithout formation or carbon:

the eiiiuent'of the intermediate reactor'at a non-peripheral point inthe end wall offsn unobstructed reactor chamber having an sidewall andanop'en outletend,the cross sectional ares of the 'open outlet e'ndbeing substantially the saine as the cross 'area of the cylindrical-reactor chamber, the intermediate reactor emuent passed into raidreactor chamber along .the longitudinal axis thereof. introducingomen-containing gas into the reactor chamber near the inlet end wallthrough a burner port. ssidburner port being so positioned sa to directthe no' or said augen-containing gas in s direction tangent to the innersurface of the side wall oi the reactor and with the predominatingcomponent of motion perpendicular to the longitu dinal axis of saidcylindrical chamber, said oxygen-containing gas and a portion of saidreactant gaseous hydrocarbon mixing to form a combustible mixture,burning the mixture to maintain the temperature of the reactor chamberat the carbon black forming temperature,

the oxygen-containing gas being introduced through said burner port at asufllclently high velocity and in suillcient quantity to maintain bycentrifugal force the flame and combustion products adJacent the wholeinner surface of the reactor chamber side wall, thus forming aseparating layer of said flame and combustion products between the sidewall of the reactor and the gaseous hydrocarbon in the reactor chamber,cooling the eilluents of the reactor chamber to below the carbon blackforming temperature and separating the carbon black from the products ofcombustion.

5. The continuous process of producing carbon black comprisingintroducing a stream o! reactant hydrocarbon in the gaseous state andreactant air at a non-peripheral point in the inlet end wall of anintermediate reactor having an inlet end wall and a generallycylindrical side wall and an open outlet end. the reactant hydrocarbonand reactant air being introduced in a direction paral icl to thelongitudinal axis of said intermediate reactor, the reactant hydrocarbonbeing greatly in stolchiometric excess of the reactant airI burning thecombustible mixture formed by the reactant air and a portion of thereactant hydrocarbon to maintain the temperature in the intermediatereactor sumciently high to crack the reactant hydrocarbon to increasethe content of the unsaturated hydrocarbons without formation of carbon:introducing the eiiluent ofthe intermediate reactor at a non-peripheralPoint in tbeend wall of an unobstructed reactor chamber having an inletend wall. a generally cylindrical side wall and an open outlet end, thecross ares oi' the open outlet end being substantially thesameas thecrosssectionalareaottiiecylin-V dried reactor chamber. the intermediate.reactor eiiiusnt being passed into said along the longitudinal ariathereof; s mixturelof gaseous fuel and atleagt'sumcientoxygen-containing ges tor combustionof said fuel into near the inlet endwall through burning the fuel-sas and sir the temnerature in the reactorchamber-attire ear- 6. The continuous process of produ carbon blackcomprising introducing a streamdngfreactanthydrocarboninthegaseousststeandx'escum: snn. s non-peripheralpoint in tbe inlet end wall oi' an intermediate reactor having an inletend wall and a generally cylindrical Bide avail and an open outlet end,the reactsnt h!- orocarbon and reactant air being introduced in adirection parallel to the longitudinal axis 0f said intermediatereactor, the reactant hydrocarbon being greatly in stoichiometric excessof the reactant air. burning the combustible mixture formed by thereactant air and a portion oi' the reactant hydrocarbon to maintain thetemperature in the intermediate reactor sumciently high to crack thereactant hydrocarbon to increase the content of the unsaturatedhydrocarbons without formation of carbon; introducing the eiiluent oithe intermediate reactor at a nonperipheral point in the end wall of anunobstructed reactor chamber having an inlet end wall. a generallycylindrical side wall and an open outlet end, the cross sectional areaof the open outlet end being substantially the same as the crosssectional area of the cylindrical reactor chamber. the intermediatereactor emuent being passed into said reactor chamber along the1ongitudinal axis thereof. introducing engen-containing gas into thereactor chamber near the inlet end wail through a burner port, saidburner port being so positioned as to direct the ilow oi saidoxygen-containing gas in a direction tangent t0 the inner surface of theside wall oi' the reactor and with the predominating component oi'motion perpendicular to the longitudinal axis of said cylindricalchamber, said oxygen-containing gas and a portion or said reactantgaseous hydrocarbon mixing to form a combustible mixture. burningthe-mixture to maintain the temperature of the reactor chamber at thecarbon black i'orming temperature, the oxygen-contaming gas beingintroduced through said burner port at a sumciently high velocity and insumeient quantity to maintain by centrifugal force the name'and-combustion products adjacent the whole inner surface of the reactorchamber side wall. thus forming a. separating layer vo! said flame andcombustion products between the side wallf-ot the reactor and thegaseous hydrocarbon in the reactor chamber. cooling' the eilluents ofthe reactor chamber to below the carbon black forming temperature andseparating the -carbon black from the products oi' combustion,

7. The continuous process ot producing carbon black which comprisesatomizing a gas-oil into a streamoi preheated reactant hydrocarbon inthe: gaseous state whereby a reactant hydrocarbon mixture is formed.introducing'the mixture oi reactant hydrocarbon at a non-peripheralpoint inthe inlet end wall oran intermediate reactor having an inlet endwall and a-generally c'ylin drical side wall-and an open outlet end. thereactant hydrocarbon mixture being introduced in a direction parallel tothe longitudinal axis of said intermediate reactor. maintaining thetemperature in the intermediate reactor sumciently high to crack thereactant hydrocarbon mixture .to increase the content ot unsaturatedhydrocarbon without formation of carbon: introducing the eiliuent oi.'the intermediate reactor at a non;

- peripheral point 4in the end wall oi' an unobstructed reactor chamberhaving an inlet end wall. a generally cylindrical side wall and an openoutlet end, the cross sectional area of the open outlet end beingsubstantially the same as the cross sectional area of the cylindricalreactor chamber, the intermediate reactor eiiiuent being passed intosaid reactor chamber along the longitudinal axis thereof, introducing amixture of gaseous fuel and at least sufficient oxygen-containing gasfor substantially complete combustion oi.' said i'uel into the reactorchamber near the inlet end wall through a burner port. burning thefuel-gas and air to maintain the temperature in the reactor chamber atthe carbon black forming temperatureI said burner port being sopositioned in the side wail oi' the reactor chamber as to direct theflow oi fuel and oxygen-contains ing gas in a direction tangent to theinner sur# tace oi' the chamber side wall and essentially perpendicularto the longitudinal axis ot said cylindrical reactor chamber. themixture of fue! and omen-containing sas being introduced through saidburner port at sufficiently high velocity and in sufficient quantity tomaintain the flame and combustion products by centrifugal force adjacentthe whole inner surface of the chamber side wail thus forming aseparating layer oi' said flame and combustion products between the sidewall and the intermediate reactor eiiluent in the reactor chamber.cooling the eiiiuents ot the reactor chamber to below the carboncracking temperature and separating the carbon black from the productsoi combustion.

8. The continuous process oi' producing carbon black which comprisesatomizing a gas-oil into a stream oi preheated reactant hydrocarbon inthe gaseous state whereby a reactant hydrocarbon mixture is formed,introducing the mixture otreactant hydrocarbon at a non-peripheral pointin the -inlet end well oi' an intermediate reactor having an inlet endwall and a generally cylindrical side wall and an open outlet endl thereactant hydrocarbon mixture being introduced in a direction parallel tothe longitudinal axis oi said intermediate reactor, maintaining thetemperature in the intermediate reactor sumciently high to crack thereactant hydrocarbon mixture to increase the content of unsaturatedhydrocarbon without formation o! carbon: introducing the eiiiuent o! theintermediate reactor at a non'vpcl'lpheral point in the end Awall oi anunobstructed reactorehamber having an inlet end wall, a generally cylinjdrical side wall and an open'outlet end. the cross sectional area ct theopen outlet end being' subi c stantially the same as the cross sectionalof the'cyiindricai reactor the intermediate reactor eiiiuent beingpassed into said reactor chamber along the longitudinal axisithereof.in.i troducingoxygen-containing gas into 4the reactor chamber near theinlet end Walltbrough a burner l port, said burner port being lopositioned as to direct the iiow of said oxygen-containinglgss'in adirection tangent to the inner surface offthe side wall of the reactorand with the`predominat` ing component of motion perpendicular tothelongitudinal axis of said cylindrical chamber. said engen-containing gasand e. portion o f said reactant gaseous hydrocarbon to form acombustible mixture, burning the mixture to maintainthe temperatureofthe reactor chamber at the vcarbon black forming temperature, the

oxygen-containing gas being introduced through;

said burner portI at a sumciently high velocity and in sufficientquantity to maintain by centrifugal i'orcc the name and combustion'-products adjacent the whole inner surface 'of the reactor chamber sidewall, thus forming a separating layer of said name and combustionproducts between the side wall of the reactor and the gaseoushydrocarbon in the reactor chamber. cooling the eiiluents oi the reactorchamber to below the carbon black form ing temperature and separatingthe carbon black from the products of combustion.

9. The continuous process of producing carbon black which comprisesatomizing a gas-oil into a stream of reactant hydrocarbon in the gaseousstate whereby a reactant hydrocarbon mixture is formed, introducing thereactant hydrocarbon mixture along with reactant air at a non-periphalpoint in the inlet end wall of an intermediate reactor having an inletend wall. a generally cylindrical side wall and an open outlet end, thereactant hydrocarbon mixture and reactant air belng introduced in adirection parallel to the longitudinal axis of said intermediate reactorthe reactant hydrocarbon mixture being greatly in stoichiometric excessoi the reactant air. burning the combustible mixture formed by thereactant air and a portion of the reactant hydrocarbon mixture tomaintain the temperature in the intermedinte reactor sulciently high tocrack the reactant hydrocarbon mixture to increase the content o!unsaturated hydrocarbons without formation of carbon; introducing theeffluent of the intermediate reactor at a non-peripheral point in theend wail of an unobstructed reactor chamber having an inlet end wall. agenerally cylindrical side wall and an open outlet end. the crosssectional area of the open outlet end being substantially the same asthe cross sectional area of the cylindrical reactor chamber, theintermediate reactor emuent being passed into said reactor chamber alongthe longitudinal axis thereof. introducing a mixture of gaseous fuel andat least sumcient oxygen-containing gas for substantially completecombustion of said fuel into the reactor chamber near the inlet end wallthrough a burner port. burning the fuel-gas and air to maintain thetemperature in the reactor chamber at the carbon black formingtemperature, said burner port being so positioned in the side wall ofthe reactor chamber as to direct the flow of fuel and oxygencontaininggas in a direction tangent to the inner surface o! the chamber side walland essentially perpendicular to the longitudinal axis of saidcyiindricsl reactor chamber. the mixture oi fuel and oxygen-containinggas being introduced through said burner port at sumciently highvelocity and in sumcient quantity to maintain the ilsme and combustionproducts by centrifugal force adls centthewhole inner surface of thechamber side wall thus forming a separating layer of said name andcombustion products between the side wall and the intermediate reactoremuent in 'theresctorchsmbeszcoolingtheemuentsoi'thereactor chamber tobelow the carbon cracking temperature and separating the carbon blackfrom the products o! combustion..

10. The continuoim process of producing'carbon blsckwhichcomprisesstomizing s gas-oilintos stream ofreactant hydrocarbon in the gaseousstate wheroby'a reactant hydrocarbon mixture is formed, introducing thereactant hydrocarbon mixture along with reactant sir st a ncnpcripheraipointintheinletendwalloflnintcrmediats reactor hsving an inietendwall. s'sencrslly cylindrical side wall and an open outlet end. thereactsnt hydrocarbon mixture and reactsnt sir being introduced in adirection'parallel to the longitudinal axis ot said intermediatereactor, the reactant hydrocarbon mixture being greatly instoichiomctric excess oi the reactant air. burning the combustiblemixture formed by the reactant slr and a portion of the reactanthydrocarbon mixturetomaintainthe temperatureintheintermediatc reactorsumciently high to crack the reactant hydrocarbon mixture to increasethe content of unsaturated hydrocarbons without formation oi carbon:introducing the eiiluent oi the intermediate reactor at a non-peripheralpoint in the end wall of an unobstructed reactor chamber having an inletend wail. a generally cylindrical side wall and an open outlet end. thecross sectional area o! the open outlet end being substantlaiiy the sameas the cross sectional area o! the cylindrical reactor chamber, theintermediate reactor eliluent being passed into said reactor chamberalong the longitudinal axis thereof, 1ntroduclng oxygen-containing gasinto the reactor chamber near the inlet end wall through s burner port.said burner port being so positioned s.; to direct the ilow of saidoxygen-containing gag 1n a direction tangent to the inner surface of theside wail of the reactor and with the predominatlng component of motionperpendicular to the longitudinal axis of said cylindrical chamber, saidoxygen-containing gas and a portion of said reactant gaseous hydrocarbonmixing to form a combustible mixture. burning the mixture to maintainthe temperature of the reactor chamber at the carbon black formingtemperature. the oxygen-containing gas being introduced through saidburner port at a suiiiciently high velocity and in suiiicient quantityio maintain by centrifugal force the name and combustion productsadiacent the whole inner surface oi the reactor cham. ber side wail,thus forming s separating layer of said name and combustion productsbetween the side wall of the reactor and the gaseous hydro.- carbon inthe reactor chamber. cooling the ements of the reactor chamber to belowthe carbon black forming temperature and separating the carbon blacktrom the products of combustion.

li. The continuous process o t producing carbon black comprisingintroducing a stream of preheated reactant hydrocarbon in the gaseousstate at a non-peripheral point in the inlet end wall ofan intermediatereactor having an inlet end wail and a generally cylindrical side walland an open outlet end. the reactant being intro duced in a directionparallel to the longitudinal axis of said intermediate reactor, furtherintroducing directly into the intermedia@ 4an atomiscd spray oi gasfoil,tenir perature in the intermediate rreactor man to emr the reltmthydrocarbon fmd atomixed gas ou to increase content 0.1731315 saturatedhydrocarbon without formation o! car.- bon; maoducinz the einen of nemex-name reactor at s non-peripheral polnt'in of an unobstructed reactorajuin.' iet end wall. s generally an open outlet end, thc mi@ -area o fthe open outlet'end being same ssthscrossscctionalsreaofthecylindricalreactor chamber. the intermediate reactor cmusnt longitudinal axisthereoi. s oi gaseous msi and st least containing gas for substantiallycome bustionofwdfuelinwthemctorsliemberwtheinlste'ndwalithroushsbumerportburningu :usi-gu ma snto the in thereactor chamber st thc blsckfcirlii` ing temperature. said burner port|9190.- tioned inthesidswslloithereactorchambcrls to direct the iiow o!fuel and Qmnecontaining gas in s direction tangent to the inner surfaceci the chamber side wall and essentially perpendicular to thelongitudinal axis oi said cylindrical reactor chamber, the mixture offuel and ongencontaining gas being introduced through said burner portst sufliciently high velocity and in suiiicient quantity to maintain theflame and combustion products by centrifugal torce adjacent the whoisinner surface of the chamber side wail thus forming a separating layerof said llame and combustion products between the side wall and theintermediate reactor emuent in the reactor chamber. cooling the emuentsof the reactor chamber to below the carbon cracking tempra ture andseparating the carbon black from the products of combustion,

i2. The continuous process oi producing carbon black comprisingintroducing a stream of preheated reactant hydrocarbon in the gaseousstate at a non-peripheral point in the inlet end wall ot an intermediatereactor having an inlet end wall and a. generally cylindrical side walland an open outlet end. the reactant hydrocarbon being introduced in adirection parallel to the longitudinal axis of said intermediatereactor. further introducing directly into the intermediate reactor anatomised spray of gas-oil, maintaining the temperature in theintermediate reactor sumciently high to crack the reactant hydrocarbonand atomised gas oil tol increase the content oi unsaturated hydrocarbonwithout ior'mation oi carbon': introducing the eiiiuent oi' theintermediate reactor at a non-peripheral point in the end wall oi anunobstructed reactor chamber having an inlet end wall, a generallycylindrical side wall and an open outlet end. the cross sectional areaof the open outlet end being substantially the same as the crosssectional aree. of the cylindrical reactos'chamber. the intermediatereactor eiuent being passed into said reactor chamber along thelongitudinal axis thereof, introducing oxygencontaining gas into thereactor chamber near the inlet md wall through a burner port. saidburnerport being so positioned as to direct the flow of said oxygen-containinggas in a direction tangent totheinneram'taoeoithesidewallotthereactorwith the psedominating component of motionperpendiculartotbelongitudinalaxisotsaidcyiinidrieaiY chamber. -saidoxygen-containing gas anda portion oi' said reactantfgaseoushydrocarbon-mixing to torm a combustible mixture. burning the mixture tomaintainthe temperature oi' the reactorchamber at the carbonblack form'-in'g temperature, the oxygen-containingv gas beingintroduced throughsaidbui'nerpoi't at a` sumcientiyhigh velocityl and in suillcientquantity to maintain by centrifugal torce the name and combustionproducts adjacent the whole inner surtace o! the reactor chamber sidewall. thus forming,`a separating layer o! saidname'and combustionproducts between tbe-aide 4wall oi the reactor and the hydrocarbon inthe reactor chamberreooling the'eiu'ents o! the reactorchambertobelovthecarbonblackiormingtemperatursLand separating the carbonblack from the products o! combustion.

'l ll."i b'e continuous process oi' producing carcomprising introducinga stream of `react'ant hydrocarbon in the gaseous state and air at' anon-peripheral point in themletend 'all of an intermediate reactorhaving an inlet end wall and a generally cylindrical side wall and anopen outletend. the reactant hydrocarbon and reactant air beingintroduced in a direction parallel to the longitudinal axis oi.' saidintermediate reactor. further introducing directly into the intermediatereactor an atomised spray o! gas-oil thus making a stoichiometric excessoi reaotantcarbon over reactant air. burningthe combustible mixtureformed by the reactant air and a portion oi the reactant hydrocarbon tomaintain the temperature in the intermediate reactor sumciently high tocrack the reactant hydrocai'bon to increase the content oi' theunsaturated hydrocarbons without formation of carbon; introducing theeiiiuent oi the intermediate reactor at a non-peripheral point in theend wall of an unobstructed reactor chamber having an inlet end wall, agenerally cylindrical side wall and an open outlet end. the crosssectional area of the open outlet and being substantially the same asthe cross sectional area of the .cylindrical reactor chamber, theintermediate reactor effluent being passed into said reactor chamberalong the longitudinal axis thereof. introducing a mixture of gaseousfuel and at least sulllcient oxygen-containing gas for substantiallycomplete combustion of said i'uel into the reactor chamber near theinlet end wall through a burner port. burning the fuel gas and air tomaintain the temperature in the reactor chamber at lthe carbon blackforming temperature. said burner port being so positioned in the sidewall of the reactor chamber as to direct the iiow ot fuel andomen-containing gas in a direction tangent to the inner surface of thechamber side wall and essentially perpendicular to the longitudinal axisof said cylindrical reactor chamber. the mixture of fuel andoxygen-containing gas being introduced through said burner port atsuniciently high velocity and in suiiicient quantity to main tain theflame and combusion products by centrifugal' i'orce adjacent the wholeinner surta of the chamber side wall thus iorming a separating layer oisaid llame and combustion products between the side wall and theintermediate reactor eiliuent in the reactor chamber. cooling theeiiluents o( the reactor chamber to below the carbon crackingtemperature and separating the carbon black from the products oicombustion.

i4. The continuous process o( producing carbon black comprisingintroducing a stream of reactant hydrocarbon in the gaseous state,andreactant air at a non-peripheral point in the inlet. end wall of anintermediate reactor having Van inlet end wall and a'generall'ycylindrical side 4g wall and an open outlet end. the reactant hydro;

carbon and reactant air being introduced in a direction parallel to thelongitudinal axisoi said intermediate reactor. furtherintroducing'directiy into the intermediate reactor anvatomised spray oigas-oil thus'making a stoichome'tric excess 'of reactant hydrocarbonover reactant air; the combustible mixture formed bythe reacta'nt airand a portion ol the reactant hydrocarbon'to maintain the temperature inthe intermediate i'eactor sumoientiy high to crsckgthe reactanthydrocarbon to increase thev content-ot theunssturated hydrocarbonswlthoutformation oi'carboh: lntl'odudnl the emuent ofthe lntrlnedlatereactor at a non-peripheral point in endvail oi an unobstructedl reactorchamberhaving an inlet end wall. a generally cylindrical 'side v all andan open outlet end. the cross sectional'axea oi the open outlet-endbeing substantially 'the same as the cross sectional area ot thecylindrical reactor chamber. the intermediate reactor eiiiuent beingpassed into said reactor chamber along the longitudinal axis thereof.introducing oxygen-containing gas into the reactor charn-A ber near theinlet end wall through a burner port. said burner port being sopositioned as to direct the iiow of said oxygen-containing gas in adirection tangent to the inner surface o! the side wall oi the reactorand with the predominatlng component oi' motion perpendicular to thelongitudinal axis o! said cylindrical chamber. said oiqgen-containi'nggas and a portion oi said reactant gaseous hydrocarbon mixing to iorm acombustible mixture, burning the mixture t0 maintain the temperature ofthe reactor chamber at the carbon black forming temperature. the

the side wall of the reactor and the gaseous hydrocarbon in the reactorchamber. cooling the 4 ellluents o! the reactor chamber to below thecarbon black forming temperature and separating the carbon black fromthe products of combustion.

JOSEPIjI C. ISREJCI.

CERTIFICATE 0F- coRREcToN.

' `Patent No. 2,575,797.

my 1,5, 19Lr5'.

JOSEPH C. KREJCI.

It is hereby certified that error appears in the printed specification vof the above numbered patent requiring correction as follows: Page '3.,'second column, Table I, eigth column thereof, sixth numeral from top,for

conducive-H page 5, Tab'le III, first column,

twelfth item fran bottoni,

and second column, line 57, for "flue" read --fuel--y 12, first column,1ine`67, for "carbon" read --hydrocarbon"; and -H column, line h, for'.'nnd" before 'being' read --end and that the said, Letters Patentshould 'be read with this correction therein lmt I may-conform to therecord of the ca Signed and sealed 1111s 16th day (Seal) se in thePatent Ofiice. of october, A. D. 1915.

Leellie, Frazer First Assistant Gamiasionior uf the side wall of thereactor and the gaseous hydrocarbon in the reactor chamber. cooling the4 ellluents o! the reactor chamber to below the carbon black formingtemperature and separating the carbon black from the products ofcombustion.

JOSEPIjI C. ISREJCI.

CERTIFICATE 0F- coRREcToN.

' `Patent No. 2,575,797.

my 1,5, 19Lr5'.

JOSEPH C. KREJCI.

It is hereby certified that error appears in the printed specification vof the above numbered patent requiring correction as follows: Page '3.,'second column, Table I, eigth column thereof, sixth numeral from top,for

conducive-H page 5, Tab'le III, first column,

twelfth item fran bottoni,

and second column, line 57, for "flue" read --fuel--y 12, first column,1ine`67, for "carbon" read --hydrocarbon"; and -H column, line h, for'.'nnd" before 'being' read --end and that the said, Letters Patentshould 'be read with this correction therein lmt I may-conform to therecord of the ca Signed and sealed 1111s 16th day (Seal) se in thePatent Ofiice. of october, A. D. 1915.

Leellie, Frazer First Assistant Gamiasionior uf

